#include <stdio.h>
double totalprice(int, double);
int main(void)
{
	int n;
	double p, bills;
	printf("Please input n and p:\n");
	scanf_s("%d%lf", &n, &p);
	bills = totalprice(n, p);
	printf("the bills is %lf", bills);
	return 0;
}
double totalprice(int g, double f)
{
	const double A = 0.8;
	double e;
	if (g >= 2) e = g * f * A;
	else e = g * f;
	return e;
    }